Stent grafts have been developed for the treatment of abdominal aortic aneurysms. An abdominal aortic aneurysm is a bulge that forms in the wall of the abdominal aorta, which is the main vessel of the arterial system of the body that extends through the abdomen. Abdominal aortic aneurysms can lose elasticity over time and rupture under normal blood pressure. A stent graft is a woven tube (graft) supported by a tubular metal stent. The stent graft is placed inside of an aneurysmal vessel to exclude the abdominal aortic aneurysm from normal blood flow and reduces pressure on the aneurysmal vessel.
Stent graft delivery systems are used to deliver the stent grafts to a deployment area inside the aorta. The stent graft can be inserted through a femoral artery and into the aorta. The stent graft can be enclosed within a sheath until the stent graft is in position at the deployment area, and then the sheath can be retracted to allow the stent graft to expand. The stent graft delivery system includes a number of complex parts because the clinician manipulates the stent graft remotely.
Presently, stent graft delivery systems include a large number of separate parts to meet the various performance requirements for stent graft deployment. For example, the sheath requires strain relief where it changes from being supported to being unsupported to prevent kinking at the transition point. The stent graft delivery system must also provide an interface near the transition point which allows the operator of the stent graft delivery system to grip and manipulate the sheath and the stent graft delivery system. The large number of separate parts must also be attached and/or connected to assemble the various parts into the stent graft delivery system. Unfortunately, the large number of separate parts required for the various functions increases manufacturing and inventory costs. Assembly time increases, increasing cost.
It would be desirable to have a stent graft delivery system that would overcome the above disadvantages.